ASP.NET下载文件

using System.IO;    'FilePath - Refers to Full Path of the file        protected void DownloadFile(string FilePath)        {            // Gets the File Name            string fileName = FilePath.Substring(FilePath.LastIndexOf('\\') + 1);            byte[] buffer;            using (FileStream fileStream = new FileStream(FilePath, FileMode.Open))            {                int fileSize = (int)fileStream.Length;                buffer = new byte[fileSize];                // Read file into buffer                fileStream.Read(buffer, 0, (int)fileSize);            }            Response.Clear();            Response.Buffer = true;            Response.BufferOutput = true;            Response.ContentType = "application/x-download";            Response.AddHeader("Content-Disposition", "attachment; filename=" + fileName);            Response.CacheControl = "public";            // writes buffer to OutputStream            Response.OutputStream.Write(buffer, 0, buffer.Length);            Response.End();        }